NUMERICAL STUDY OF THE EFFECTS OF WALL CATALYSIS ON SHOCK-WAVE BOUNDARY-LAYER INTERACTION

This article presents a numerical study to investigate the effects of nonequilibrium chemistry, and in particular, wall catalysis on the sep arated flow region generated by an oblique shock wave impinging upon a flat plate boundary layer for a highly dissociated air flowfield. The results focus on the effects of the nonequilibrium chemistry upon the surface heat transfer and the separation zone size. Comparative resul ts are given for chemically reacting (both noncatalytic and fully cata lytic walls) and nonreacting flow cases. Furthermore, this comparison is extended over a wide range of freestream pressures (143-123,500 Pa) with a constant Reynolds number, Re = 1793. A direct comparison of al l three cases, at low pressures, reveals a minimal change in the peak heat transfer for the noncatalytic wall case as compared to the calori cally perfect gas case. In contrast, the fully catalytic wall exerted a tremendous increase in the surface heat transfer. However, as the fr eestream pressure is increased, significant recombination occurs, so t he increase in the peak heat transfer for the noncatalytic wall is mor e pronounced. Whereas for the fully catalytic wall, at higher pressure s, the increase in peak heat transfer is somewhat diminished due to th e chemical recombination upstream of the reattachment point.